What are Cold Seeps and Hydrothermal Vents?
Cold seeps and hydrothermal vents are structures found on the ocean floor that support biomes completely independent of the Sun’s energy. Cold seeps slowly release hydrogen sulfide, methane and other hydrocarbon-rich fluids, while hydrothermal vents release geothermally heated water rich with the same dissolved minerals. As the ocean floors are typically 2-3 miles (3.2 – 4.8 km) from the surface, these biomes are completely dark for millions of years. They are also heavily pressurized due to the weight of the water above — hydrothermal vent and cold seep biomes usually have an ambient pressure a couple of hundred times greater than at the surface. Cold seeps and hydrothermal vents are the only long-term biomes whose primary producers do not depend on photosynthesis. Instead of photosynthetic bacteria or plants forming the backbone of the ecosystem, this function is served by chemotrophic bacteria and archaea, which have close symbiotic relationships to heterotrophic organisms which con
